| 초록 |
We present a unique approach to quantitative nanoscale grafting of polymer chains to the surface on the nanometer scale using a reactive diblock copolymer. The block copolymer is comprised of poly(styrene) (PS) and poly[3-(triethoxysilyl) propyl isocyanate] (PIC). The PIC block contains a surface-reactive alkoxy silyl side groups which can anchor to the SiO2 substrate surface. The composition and molecular weights of the two copolymers investigated were PIC(23K)/PS(39K) and PIC(23K)/PS(200K). These copolymers can be readily grafted onto silica substrate surfaces by simple solution immersion method, yielding nanopatterns of polystyrene mounds. The distance between PS mounds and the number of polymer chains per mound was strongly dependent on the molecular weight of PS block. The average mound-to-mound distance for the PIC(23K)/PS(200K) was about 250nm, while that for the PIC(23K)/PS(39K) was only about 80nm. The large difference in the mound distance between the copolymers having the same PIC molecular weights, indicates that the adsorption of the polymer chains are strongly affected by the steric effect of PS blocks during the adsorption. We expect that once the area between the polymeric mounds is functionalized further, this surface property can be controlled by expansion or contraction of the bound polymer chains over the area. |
